Ball-and-socket joints of said type are known in the art and are preferably used in motor vehicles. The ball head of the ball-and-socket joint is rotatably and tiltably supported in the bearing shell, and the bearing shell in turn is arranged in the joint housing.
The purpose of the bearing shell, which is usually exposed to hard wear, is to compensate the lateral forces acting on the ball-and-socket joint and to absorb shocks to the joint housing and to the ball pivot. The bearing shell is therefore advantageously made of an elastic plastic that can be elastically deformed as a result of the forces acting on the ball-and-socket joint.
To ensure that the ball head is not enclosed too tightly by the bearing shell during assembly of a ball-and-socket joint of the initially mentioned type and that the joint is not too stiff, tight manufacturing tolerances are required particularly in the production of the joint housing. To compensate stiffness of the ball-and-socket joint due to imprecise manufacturing tolerances, a bearing shell has been proposed, which at one end face is provided with very small projections whose height slightly exceeds the manufacturing tolerances of the joint. These projections are deformed when correspondingly high forces are applied as the joint is assembled and have the purpose of compensating the manufacturing tolerances of the joint members such that the tolerance for free movement of the ball-and-socket joints can be kept within limits. However, wear of the bearing shell cannot be compensated by these projections.
With increasing wear of the bearing shell, an undesirable, continuously increasing bearing clearance develops between ball head and bearing shell. With respect to the operating life of the ball-and-socket joint this causes a change in the motive torques of the bearing journal as well as a continuous change in the elasticity properties of the bearing shell. As a consequence, the bearing is no longer exact, which results in imprecise wheel guidance of the ball-and-socket joint and noise development.
Thus, based on this prior art, the object of the present invention is to further develop a ball-and-socket joint of the initially mentioned type to reduce the tolerance of free movement and increase the life of the ball-and-socket joint while simultaneously simplifying the assembly.